7
11. Calibration
Your transmitter has been factory calibrated to meet or exceed the
specifications outlined in this manual. To maintain original
specifications it is generally recommended that your transmitter be re-
calibrated on an annual basis depending on operating conditions.
12. Calibration Procedure for HX93AC (all styles)
Relative Humidity Adjustment
Recommended equipment:
• Humidity Calibration Kit, OMEGA
®
Model No.:
HX92-CAL
• Handheld Digital Multi-meter, OMEGA
®
Model No.:
HHM29
• Dc Power Supply, OMEGA
®
Model No.:
PSU-93
1. Remove enclosure cover
2. Connect transmitter as shown in figure below.
3. Apply power to transmitter and allow to warm up for 15 min.
4. Place unit in a 11% RH environment and allow to stabilize for 15 min.
5. Adjust potentiometer “P1” for a output reading of 5.76 mA
6. Place unit in a 75% RH environment and allow to stabilize for 15 min.
7. Adjust potentiometer “P2” for a output reading of 16.0 mA
8. Repeat steps 4, 5, 6, and 7 as necessary until proper readings are maintained.
9. Calibration complete.
Figure 6 - HX93AC Calibration Procedure
Relative Humidity Adjustment
16.00 mA
TB1
TB2
24V
PSU-93
HHM29
SENSOR HEAD
10A uAmA COM V
HX92-CA
CALIBRATION BOTTLE
P1 P3
P2
+
–
12
3
12
3
11
HX93A, HX93DA SERIES
RH/Temperature Transmitter
NOTE:
Do not adjust
P3. This is a
factory
setting.